After 18 months of negotiations, the mainland arm of retail giant Wal-Mart Stores signed a collective agreement with the company's Shenzhen union yesterday to provide improved benefits for its 8,500 employees there. The agreement includes an annual December review of salaries and an expected 9 per cent average pay rise for the year 2008/2009 as well as a 1 per cent pay rise for those who get promoted. The company also agrees to pay more than the Shenzhen government minimum wage. The agreement also settled requirements on working hours and holidays.